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TCH-300
TROUBLESHOOTING
c
CD Function
CD PART
Select
NO
Is power turned ON? m Check power supply circuitry.
I
YES
I 1 .- .
-
NO
Does initial reading occur? w Check laser circuitry.
I .
YES
+ Check focusing circuitry.
w Check disc.
$
- NO
Can disc be played? w Check tracking servo circuitry.
.
YES
NO
Is audio output supplied? Check Audio circuitry.
YES
I
OK
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TCH-300
(1) If display LCD lighting is not normal
I CD Function Select I
(WITHOUT DISC)
NO Check voltage in the power
Do display LCD then light?
* supply circuitry.
I
YES
1
Is u-COM IC401 reset circuit Reset circuit defective.
normal? Pin @ NO Surrounding circuit defec-
tive.
YES
I
Is u-COM IC401 C.L.K
terminal Pin @ (OSC) NO C405, C406 defective.
input? X401 defective.
about 0.25ysec w
YES
I
I
Is IC401 8, @ output
waveform normal? NO Pattern defective.
YES
1
Is IC401 Pin @ output
waveform normal? NO Pattern defective.
YES
Display defective.
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ITCH-300
(2) If initial reading is not carried out (with Disc)
1
Is IC401 Pin @output NO
Does disc motor rotate? waveform normal? Leaf SW contact defective.
1 Connector defective.
YES Pattern short.
Ic4" @%6-j DOOR CLOSE
YES
I
NO
Does laser light? )8
Is RF wave Is tracking servo Is signal output Is signal
IC601 defective.
output? NO op.erating? NO at TEI? NO output, NO
Connector
- Is the lower at IC601
RF defective.
envelope of RF Pin @?
Pick-up defec-
waveform flat? tive.
YES
YES
Pattern
YES - defective .
I
Is signal output at tracking output NO IC601
IC601 Pin @? defective.
IC601 Pin @waveform Pick-up
YES 1 defective.
Connector
defective.
Is rotation normal? Does IC602 Pin @(LKFS) as
Is there any irregularity in figure?
frequency? NO
YES
1
Is HF signal normal without
dropout?
NO Disc initial reading damaged
w or defective.
YES
w Disc defective.
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When laser does not light.
I
Is below signal "L" at IC401
Pin@(PZAPC)?
C
YE L ;
IC401 defective.
YES YES
1
Is below signal output at NQ
IC602 Pin @, @?
Does pick-up stop after
having moved to the
Are detect output input at
IC601 Pin @?
I IC601 defective.
innermost position? IC602
Pin @. I b
NO
NO PZLSW defective.
Connector defective.
-i
YES
IC603 defective. I
_ 1 IC601 defective.
v Surrounding circuitry defective.
YES
I
1 NO w Connector defective.
Has laser power source
l;ty~totheQ601~ 1
(Q601 collector voltage about
YES
Flow laser current?
-
Both voltage of Q601 is about ,,,Q YES Laser defective.
1 .OV? b R602M.OV
b Connector defective, short etc.
\
- 30 -
TCH=300
@I When laser lights.
I
Is signal output at focus search NO
Do lenses move up and down? IC601 defective.
terminal?
C621 defective.
YES
I IC601 Pin @I (FEI)
I
YES
I
Is signal output at IC601 Pin
@?
Insert disc and YES 1
Actuator short.
in the case of
check of initial Connector short.
leading.
q
NO Connector short.
IC601 defective.
YES
The waveform of RF (HF) isI
below figure?
I NO Turntable height error.
Laser diode degraded.
Is Fok signal output?
RF (HF and REF) 0.4V over No
Is Fok signal input to IC401 Pin @ No
(PFOK)? Pattern defective.
rl
-31-
TCH-3001
YES
I
Is FE1 signal output?
IC601 Pin @ . IC601 defective.
NO
Pick-up defective.
Connector defective.
\8 *0
\8 *`
==P- \. l
8
YES
Is FEI signal output at IC601 Pin @
(ISTAT)? NO When Fok focus
IC601 defective.
Servo Conform by
FZC signal.
FEI
\\ ,I
\' ,I -
,
SENSE 3
_I
Is Mon signal output by Pattern defective
IC602 Pin @ ? NO between IC701 Pin @, -
@ @@and IC401.
Is MDP signal output by
IC602 Pin @ ? III
III1 III
YES
I
IC601, 603 defective.
Has voltage at disc motor? Surrounding circuitry
NO
defective.
YES
Disc Motor defective.
Connector defective.
TCH-300
AUDIO CHECK
Power circuit check
.-
NO NO
Is output? b Is each voltage normal? * Power source, Pattern check.
YES
Is signal
@,@?
returned at IC602 Pin
@ : 88.2kHz
-4 NO IC602
circuitry.
defective surrounding
@: 4.3218MHz
YES
1
Is signal output at IC602 Pin @ , NO IC602 defective.
@? Surrounding circuitry.
YES (
Is "L" at IC602 Pin @? NO
Pattern defective between IC401
Pin @and IC602 Pin @ .
YES
1
Is signal output at IC301 Pin @ IC301 defective.
@,@,@,@,@,@? Pattern defective.
YES
I
Audio check OK.
- 33 -